Unlike other species of the same family, which travel above the ground

Question

Unlike other species of the same family, which travel above the ground level by swinging from branches and vines, the Tyruvian flying monkey has a skin membrane connecting its limbs that allows it to glide from tree to tree. Based on the fact that the chief predator feeding on monkeys in Tyruvian jungles, the striped panther, cannot climb trees, researchers have hypothesized that the flying monkey population is continuously increasing in numbers while the populations of other species remain stable.

The researchers' conclusion relies on which of the following assumptions?

The researchers' conclusion relies on which of the following assumptions?

(A) The striped panther, being the most powerful of the Tyruvian jungle inhabitants, has extremely developed hindleg muscles which allow it to leap to a great height, although it rarely can reach the altitudes of the flying monkey's habitat.

(B) The Tyruvian flying monkey's webbed limbs allow downward parachuting or even horizontal gliding but are not designed to enable it to soar upwards when fleeing from earthbound predators.

(C) As opposed to some of the other species in its family that cannot avoid descending to the ground from time to time, the Tyruvian flying monkey subsists mostly on food sources that grow high above ground level and abundantly enough to sustain any number of such animals.

(D) While the striped panther is too heavy or large-bodied to be able to safely climb trees around the habitats of Tyruvian flying monkeys, there are other predators who may prey on such monkeys.

(E) Having skin between its limbs does not make the Tyruvian monkey any less nimble while leaping from tree to tree, but it does affect its ability to maneuver on the ground and climb trees quick enough so as to elude predators.

Bunuel · Accepted Answer

Official Explanation

Unlike other species of the same family, which travel above the ground level by swinging from branches and vines, the Tyruvian flying monkey has a skin membrane connecting its limbs that allows it to glide from tree to tree. Based on the fact that the chief predator feeding on monkeys in Tyruvian jungles, the striped panther, cannot climb trees, researchers have hypothesized that the flying monkey population is continuously increasing in numbers while the populations of other species remain stable.

The researchers' conclusion relies on which of the following assumptions?

The researchers' conclusion relies on which of the following assumptions?

(A) The striped panther, being the most powerful of the Tyruvian jungle inhabitants, has extremely developed hindleg muscles which allow it to leap to a great height, although it rarely can reach the altitudes of the flying monkey's habitat.

Incorrect.

This is an Assumption question, in which you are requested to find an assumption that connects the premises with the conclusion:

Premise A: most monkeys travel by swinging from branches, but the flying monkey glides
 +
Premise B: most monkeys are eaten by the striped panther
 +
Premise C: the striped panther cannot climb trees
 +
Assumption: ?
 =
Conclusion: flying monkeys population are constantly growing, while other monkeys are not

Now ask yourself: the researchers believe flying monkeys will grow in number, based on the fact that the striped panther can't get to them. But what must assumed for this to be true?

The assumption has to explain why the researchers thought the panther will not reach the flying monkeys but will reach other monkeys. However, to draw the conclusion based on the premises, the researchers did not need to assume anything specific about the panther's biology. While this answer choice provides new information about the striped panther's hindleg muscles, which might explain why the panther reaches other monkey species but not the Tyruvian flying monkey species, the developed hind leg muscles are not a necessary assumption.

(B) The Tyruvian flying monkey's webbed limbs allow downward parachuting or even horizontal gliding but are not designed to enable it to soar upwards when fleeing from earthbound predators.

Incorrect.

First, this answer choice provides new information while we are looking for an assumption, the unfounded step the author made between the premises and the conclusion. Moreover, you could have eliminated this answer choice based on the fact that it weakens the conclusion - it claims the monkey can be caught by ground predators such as the striped panther. Remember - the assumption must always agree with the conclusion.

(C) As opposed to some of the other species in its family that cannot avoid descending to the ground from time to time, the Tyruvian flying monkey subsists mostly on food sources that grow high above ground level and abundantly enough to sustain any number of such animals.

The researchers must have assumed that there is a fundamental difference between the flying monkey and other species that prevents the striped tiger from getting to the flying monkey. The first part of this answer choice is already known to us: the panther preys on other types of monkeys; since the striped panther always remains on the ground it follows that these monkeys must descend.

As for the assumption, for the flying monkey population to keep growing, the researchers must at the very least assume it has enough food and that it is well beyond the reach of the striped panther.

As for the assumption, for the flying monkey population to keep growing, the researchers must at the very least assume it has enough food and that it is well beyond the reach of the striped panther.

(D) While the striped panther is too heavy or large-bodied to be able to safely climb trees around the habitats of Tyruvian flying monkeys, there are other predators who may prey on such monkeys.

Incorrect.

This is an Assumption question, in which you are requested to find an assumption that connects the premises with the conclusion:

Premise A: most monkeys travel by swinging from branches, but the flying monkey glides
 +
Premise B: most monkeys are eaten by the striped panther
 +
Premise C: the striped panther cannot climb trees
 +
Assumption: ?
 =
Conclusion: flying monkeys population are constantly growing, while other monkeys are not

Now ask yourself: the researchers believe flying monkeys will grow in number, based on the fact that the striped panther can't get to them. But what must assumed for this to be true?

First, this answer choice provides new information while we are looking for an assumption, the unfounded step the author made between the premises and the conclusion.

Notice that this answer choice also weakens the conclusion as it provides a reason why the flying monkey population will not grow. However, the assumption must always agree with the conclusion.

(E) Having skin between its limbs does not make the Tyruvian monkey any less nimble while leaping from tree to tree, but it does affect its ability to maneuver on the ground and climb trees quick enough so as to elude predators.

Incorrect.

This answer choice is illogical. If the author had assumed that the flying monkey's extra skin prevented it from escaping his predators (leading to its death), then he or she wouldn't have concluded that the flying monkey population is constantly growing.

sumitkrocks · Answer

(A) The striped panther, being the most powerful of the Tyruvian jungle inhabitants, has extremely developed hindleg muscles which allow it to leap to a great height, although it rarely can reach the altitudes of the flying monkey's habitat.
 Yes- if by jumping, It could reach the flying monkey's habitat, it is very likely that it would have attacked monkey and caused significant reduction in the count. 
Keep this option

(B) The Tyruvian flying monkey's webbed limbs allow downward parachuting or even horizontal gliding but are not designed to enable it to soar upwards when fleeing from earthbound predators.
 How does it exactly help Monkey from being attacked by panther ? -Eliminate

(C) As opposed to some of the other species in its family that cannot avoid descending to the ground from time to time, the Tyruvian flying monkey subsists mostly on food sources that grow high above ground level and abundantly enough to sustain any number of such animals.

Time to time means frequently, so this option gives some hint that not frequently but flying monkey does come to ground and hence a likely risk of an attack by panther. 
 
(D) While the striped panther is too heavy or large-bodied to be able to safely climb trees around the habitats of Tyruvian flying monkeys, there are other predators who may prey on such monkeys.
 Out of scope

(E) Having skin between its limbs does not make the Tyruvian monkey any less nimble while leaping from tree to tree, but it does affect its ability to maneuver on the ground and climb trees quick enough so as to elude predators.
 Irrelevant

B/W A and C i think A is more closer to be correct

winterschool · Answer

Unlike other species of the same family, which travel above the ground level by swinging from branches and vines, the Tyruvian flying monkey has a skin membrane connecting its limbs that allows it to glide from tree to tree. Based on the fact that the chief predator feeding on monkeys in Tyruvian jungles, the striped panther, cannot climb trees, researchers have hypothesized that the flying monkey population is continuously increasing in numbers while the populations of other species remain stable.

The researchers' conclusion relies on which of the following assumptions?

The researchers' conclusion relies on which of the following assumptions?

(A) The striped panther, being the most powerful of the Tyruvian jungle inhabitants, has extremely developed hindleg muscles which allow it to leap to a great height, although it rarely can reach the altitudes of the flying monkey's habitat.  Incorrect

but there is possibility that striped panther can hut flying monkey and decrease its numbers

(B) The Tyruvian flying monkey's webbed limbs allow downward parachuting or even horizontal gliding but are not designed to enable it to soar upwards when fleeing from earthbound predators.  Incorrect

weakens argment

(C)  As opposed to some of the other species in its family that cannot avoid descending to the ground from time to time, the Tyruvian flying monkey subsists mostly on food sources that grow high above ground level and abundantly enough to sustain any number of such animals .  Correct

no chance to hunt by striped panther, so its number must increase
 
(D) While the striped panther is too heavy or large-bodied to be able to safely climb trees around the habitats of Tyruvian flying monkeys, there are other predators who may prey on such monkeys.  Incorrect

weakens argument
 
(E) Having skin between its limbs does not make the Tyruvian monkey any less nimble while leaping from tree to tree, but it does affect its ability to maneuver on the ground and climb trees quick enough so as to elude predators.  Incorrect

weakens argument

IanStewart · Answer

I can guess the intended answer is C here; the conclusion distinguishes flying monkeys from other monkeys, and suggests flying monkey populations will grow, while other monkey populations will not, because flying monkeys are not vulnerable to panther predators, while, presumably, all the other monkeys are.

But all of the answers here are far too factually specific to be "assumptions". C is not an assumption. It's really just something that would, if true, make the conclusion more plausible. Answer C does not need to be true for the argument to be valid. We don't need to assume, for example, that the flying monkey feeds on things "high above ground level". If panthers can't climb trees, presumably food a few feet above ground level would be inaccessible to panthers. And we don't even need to assume flying monkeys feed on food above ground level at all. Provided they spend little time on the ground (just long enough to get food) while other monkeys spend lots of time on the ground, the flying monkey will be significantly less susceptible to predation than other monkeys. The conclusion still follows even if C is not true.

Sumi1010 · Answer

Tyruvian flying monkey has some favor to glide from tree to tree, while other species of the same family swing from branches. The chief predator feeding on monkeys cannot climb on trees.
 Conclusion :  The flying monkey population is continuously increasing in numbers while the populations of other species remain stable.

The arguments needs multiple assumptions to stand with its conclusion. 
1. The Tyruvian flying monkey mangages to save itself from the chief predator often (not just at the heights).
2. Tyruvian flying monkey population is not impacted by any other factor than the chief predator.
3. The chief predator does not consume other species.

Let's look at the choices now.

(A) The striped panther, being the most powerful of the Tyruvian jungle inhabitants, has extremely developed hindleg muscles which allow it to leap to a great height,  although it rarely can reach the altitudes of the flying monkey's habitat. 
 The all that we know (need to know) is that the panther fails to catch the flying monkeys at height. 
What else can it mange is futile. 
(B) The Tyruvian flying monkey's webbed limbs allow downward parachuting or even horizontal gliding but are  not designed to enable it to soar upwards  when fleeing from earthbound predators.
 This is something that can't be assumed for the given conclusion to hold. 
(C) As opposed to some of the other species in its family that cannot avoid descending to the ground from time to time, the Tyruvian  flying monkey subsists mostly on food sources that grow high  above ground level and abundantly enough to sustain any number of such animals.
 In-line with 1st assumption that the monkeys don't have to come down and hence chances for the predator is minimal.  
(D) While the striped panther is too heavy or large-bodied to be able to safely climb trees around the habitats of Tyruvian flying monkeys,  there are other predators who may prey on such monkeys. 
 This information actually weakens the argument. 
(E) Having skin between its limbs does not make the Tyruvian monkey any less nimble while leaping from tree to tree,  but it does affect its ability to maneuver  on the ground and climb trees quick enough so as to elude predators.
 The 1st part is an assumption(defensive), but 2nd part limits the movement of the monkey. 
If so, it weakens the argument.

IMO  C

mSKR · Answer

Conclusion : flying monkey population is continuously increasing in numbers while the populations of other species remain stable.

B, D and E weakens the conclusion. 
For assumption question, we need to find which option can strengthen the option.

A and C are shortlisted.
I choose C because C explains why T F monkeys increase but other monkeys need to go down and stay stable but not increase. A option doesn’t talk about the effect on other species.

Hence C is the correct answer.

HarshaBujji · Answer

(A) The striped panther, being the most powerful of the Tyruvian jungle inhabitants, has extremely developed hindleg muscles which allow it to leap to a great height, although it rarely can reach the altitudes of the flying monkey's habitat.
 OFS, Irrelavent

(B) The Tyruvian flying monkey's webbed limbs allow downward parachuting or even horizontal gliding but are not designed to enable it to soar upwards when fleeing from earthbound predators.
 OFS

(C) As opposed to some of the other species in its family that cannot avoid descending to the ground from time to time, the Tyruvian flying monkey subsists mostly on food sources that grow high above ground level and abundantly enough to sustain any number of such animals.
 Yeah, If we negate this it will shatter the conclusion

Negated Stmt :  Tyruanvain flying monkey cannot avoid descending to the ground from time to time. 
Then it's the ability to fly has nothing to do with protecting it from predators as it mostly stays on the ground like all other species

(D) While the striped panther is too heavy or large-bodied to be able to safely climb trees around the habitats of Tyruvian flying monkeys, there are other predators who may prey on such monkeys. OFS, But this also weakens the reasoning.

(E) Having skin between its limbs does not make the Tyruvian monkey any less nimble while leaping from tree to tree, but it does affect its ability to maneuver on the ground and climb trees quick enough so as to elude predators. OFS, Irrelavent

IMO C

princevora · Answer

the conclusion distinguishes flying monkeys from other monkeys, and suggests flying monkey populations will grow, while other monkey populations will not, because flying monkeys are not vulnerable to panther predators, while, presumably, all the other monkeys are. but what if there is another predator who will kill them, then the population will not grow and thus conclusion falls apart. so why is C a better answer then D.

Unlike other species of the same family, which travel above the ground

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Unlike other species of the same family, which travel above the ground

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